This application claims the priority of Japanese Patent Application No. 9-242120 filed on Aug. 21, 1997, and Nos. 9-282542 and 9-282541 filed on Sep. 30, 1997, and No. 9-281398 filed on Sep. 16, 1997 which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to an opening/closing controller for opening/closing a pipe such as an air feed pipe, water feed pipe, and suction pipe disposed in an endoscope and a flow rate controller for controlling a flow rate.
2. Description of the Prior Art
FIG. 10 shows a configuration of a conventional endoscope and an electromagnetic valve unit. In FIG. 10, a water feed pipe 2A, an air feed pipe 3A, and a suction pipe (also used as a treatment tool inserting channel) 4A are disposed from a distal end section 1A to an operating section 1B in an endoscope 1, and the suction pipe 4A is connected to a forceps port 5 disposed in the operating section 1B. As shown in FIG. 10, the operating section 1B is provided with an air/water feed (A/W) switch 6, which is a two-stage switch, a suction (SUC) switch 7, and a photographing button 8. The operation control signals of the switches 6 and 7 are supplied to an electromagnetic valve unit 9 via signal lines (not shown). Also, in order to connect the electromagnetic valve unit 9 to the operating section 1B, a water feed pipe 2B, an air feed pipe 3B, and a suction pipe 4B are provided in a cable or the like.
The electromagnetic valve unit 9 is provided with five electromagnetic valves Va, Vb, Vc, Vd and Ve for opening/closing each of the pipe, a pump 62, a control section 63, and a feed water tank 28. The feed water tank 28 is connected to the pump 62 via an air feed pipe 3C, and also connected to the electromagnetic valve Va via a water feed pipe 2C. Further, a suction pipe 4C is connected with a suction tank 29 and a pump.
According to the above-described configuration, when the air/water feed switch 6 is not operated, only the electromagnetic valve Vc is opened. By closing the electromagnetic valves Va and Vc and opening Vb, air is fed to an air feed pipe 3, and by closing the electromagnetic valves Vb and Vc and opening Va, water is fed to a water pipe 2. By this air/water feed, contamination etc. of an objective lens window disposed in the distal end section 1A can be removed. Also, by closing the electromagnetic valve Ve and opening Vd, suction is effected, whereby the content etc. in a body being observed are sucked and discharged via a suction pipe 4. It is to be noted that endoscope systems controlling the fluid by using the above-mentioned electromagnetic valves have been disclosed in Unexamined Japanese Patent Application Laid-Open Nos. 1-297045, 1-310638, etc.
As the above-mentioned electromagnetic valves Va through Ve, a pinch valve, for example, is used. This pinch valve closes the pipe by crushing the soft pipe portion of each pipe arranged in the valve, and opens it by releasing the crushed state. Such a pinch valve has an advantage that an opening/closing portion is not clogged with dirt etc., and a cleaning brush can be caused to pass through a valve portion, so that the pipe inside can be cleaned easily.